Question

Which amino acid is used to synthesise Nitric oxide ?

• A. glycine
• B. arginine
• C. tyrosine
• D. threonine

Answer 1

The Correct Option is B

Nitric oxide (NO) is a significant signaling molecule in various physiological processes. It is synthesized from the amino acid arginine. The enzymatic reaction that converts arginine to nitric oxide is catalyzed by nitric oxide synthase (NOS). During this conversion, arginine is oxidized, leading to the production of nitric oxide and another compound called citrulline.

This reaction can be summarized by the following chemical equation:
L-arginine + NADPH + O₂ → nitric oxide + L-citrulline + NADP⁺
In this equation, NADPH (nicotinamide adenine dinucleotide phosphate) acts as a reducing agent, and oxygen (O₂) is also required for the reaction to proceed.

Considering the options provided:

• Glycine
• Arginine: This is the correct choice as it is directly involved in nitric oxide synthesis.
• Tyrosine
• Threonine

The amino acid responsible for synthesizing nitric oxide is arginine. This plays a crucial role in various biological functions, including vasodilation and neurotransmission.